I recently had a clients older site stop working with CKfinder 18.104.22.168 and IE11. Here’s how that worked out ….
I modified ckfinder.html line 36 from
var sSuffix = /msie/.test(navigator.userAgent.toLowerCase()) ? ‘ie’ : ‘gecko’;
var sSuffix = /trident/.test(navigator.userAgent.toLowerCase()) ? ‘ie’ : ‘gecko’;
I then found IE needed to be running with compatability, so into the header goes
<meta http-equiv=”X-UA-Compatible” content=”IE=9″ />
This got it working, although there’s still something screwy about the hight calculations when it does load.